C150 landing approach trim

455 Bravo Uniform

455 Bravo Uniform

Final Approach
Joined
Aug 18, 2015
Messages
5,769
Location
KLAF
Display Name
Display name:
455 Bravo Uniform
I go to landing config abeam on downwind (carb heat, 1600rpm, flaps 1), turn base and go flaps 2, and turn final flaps 3 as needed. I've just figured out over time to go 1 turn of trim down abeam the numbers, and then I'm good to touchdown.

Does anyone trim like below? It has the same effect as my being 1 turn down by the time final comes around (4 up, 3 down). I guess I could experiment at altitude, but this is a forum, so hey.

http://www.pilotfriend.com/training/flight_training/fxd_wing/cessna150.htm

Snippet:
LANDING (C-150)
Prelanding check( Go-around procedure)
Abeam the numbers:
Cruise power/IAS
Carb Heat
Pwr 1500/1700
Hold heading/alt
Trim Down 3
Fly 60/70
10 degree flaps 1-2-3-4-
Yoke forward
Trim UP 1
Fly 60/70
Pwr 1500
Clear
Turn base
20 degrees 1-2-3-4
Yoke forward
Trim UP 1
Fly 60/70
Pwr 1500
Clear
Turn final
Full flaps 1-2-3-4-5-6-
Yoke more forward
Trim up l (172 no change)
Fly 60/60
 
Hey works for you, great. I teach trim to maintain the airspeed, and your method seems pretty close to what I recall from my C150-152 days. Just keep in mind the trim you may have to overcome if you go around.
 
Flying by the "numbers" is a good way for someone new to get acquainted quickly but I find it best to teach - move whatever control you need to move in whatever amount you need it in order to achieve the desired results. In other words, your step by step linear mechanical approach will only work under XXX conditions, there is an art to flying and it takes time to master no matter what.
 
It's like learning to dance, sure you can do it completely paint by numbers, but it's really not the best way.

Just trim the pressure off the controls.
 
well,,, if its rigged correctly full down trim will give best glide so there is a little science going on :p
 
jaybee said:
well,,, if its rigged correctly full down trim will give best glide so there is a little science going on :p
Click to expand...
Not with the flaps down.

Full nose up when clean will give you something approximating best glide.

The trim strategy I use is typically to trim for a 500 FPM descent in all configurations, at 1500 RPM. In a 172, that gets a nice short field landing with a final approach speed very close to 60 KIAS. It even works in a 177 or 182 if you change 1500 RPM to 15 inches.

Adjust throttle to make the aim point once on final, at full flap. In a lot of wind, additional throttle will be needed. If it's dead calm, you'll need to remove some.

There are a lot of ways to do this. My strategy isn't conventional, but it's sure nice for establishing early descent and preventing the common high-on-final scenario.
 
Last edited:
I used to trim for 80.. one turn of trim started when my instructor recommended this when flying an ILS. Works great.

Sent from my Nexus 7 using Tapatalk
 
well since we are picking nits, I said best glide... don't think I ever put flaps in while trying to achieve best glide... not sure why you even brought up what I said at all...

now you will say but the OP blah blah... I was responding to the science behind it that Jordane referred to and well since this is the PoA and 5 posts have previously occurred then going off on a tangent is not only appropriate but mandatory per forum rule Chap17 Subchapter D para 7
 
As the OP, I make a motion to allow this thread to go off on a tangent, as long as it's allowed to go back at will and no one gets us locked out, lol. Per Ch. 17, subch D, para 7.
 
455 Bravo Uniform said:
Does anyone trim like below? It has the same effect as my being 1 turn down by the time final comes around (4 up, 3 down). I guess I could experiment at altitude, but this is a forum, so hey.
Click to expand...
Not me.

I am very much a fly by numbers guy, teaching pitch/power/configuration and target settings from the very first lesson. So your description of targeting certain rpm and airspeed and incrementally adding flaps from downwind to landing makes absolute sense to me.

But trying to target "x" turns of the trim wheel rather than establishing a configuration, feeling the control pressures and using trim to remove them strikes me as way too mechanical and, even to some degree as a poor technique in the long term.
 
Last edited:
In my 172, I cut power abeam the numbers, pull for best glide and trim up 3 immediately. Then flaps 1, turn base, flaps 2, flaps 3-4 on final.

This causes me to hold a great deal of forward pressure on final that I release gradually through the flare, landing with the yoke pulled back to the stops.

Your ego adjustments welcome.
 
I make it extremely simple (and it should be said that I'm at a nontowered field with lots of slow rag-and-tube aircraft, so no need to come into the pattern/expedite final at warp speed).

Full flaps before entering the pattern....fly pattern at 70 to 75 KIAS at about 1750 rpm to maintain TPA.
Throttle back to about 1400 rpm abeam the numbers, which gives me the proper sink rate without having to re-trim.
Trim up and reduce power on final to give an over-the fence speed of 60-63 KIAS.
Land.

Wipe all the bugs off the leading edges and windscreen, and call it a day.
 
whereisrandall said:
In my 172, I cut power abeam the numbers, pull for best glide and trim up 3 immediately. Then flaps 1, turn base, flaps 2, flaps 3-4 on final.

This causes me to hold a great deal of forward pressure on final that I release gradually through the flare, landing with the yoke pulled back to the stops.

Your ego adjustments welcome.
Click to expand...
and as you are holding all that forward pressure and you need to go around and add power what happens then?

trim lesson 1, use controls to establish what you want, use trim to remove control pressures. end of procedure.

bob
 
whereisrandall said:
In my 172, I cut power abeam the numbers, pull for best glide and trim up 3 immediately. Then flaps 1, turn base, flaps 2, flaps 3-4 on final.

This causes me to hold a great deal of forward pressure on final that I release gradually through the flare, landing with the yoke pulled back to the stops.

Your ego adjustments welcome.
Click to expand...

I'm genuinely curious...

...is this something you were taught or had demonstrated to you somewhere along the line, or did you come up with it yourself?

It's quite unconventional, and there are numerous reasons why. But if you've stumbled on something that works for you, far be it from me to argue with success!
 
FastEddieB said:
Flying the trim" is generally thought to be bad form and an impediment to precise flying
Click to expand...

What would that look like? Putting in trim to start a climb or descent? I trim to the airspeed I want on final, and in that case I'm not trimming out stick forces necessarily. But otherwise I constantly trim to relieve the pressure.
 
@FastEddieB - I'm guessing you're wondering about the extreme trim - for the forward pressure required on landing and go-around?

I was taught this method by my primary instructor, a high-time CFI. His rationele was to learn to dead-stick every landing (your mileage may vary in other aircraft) so that it's second nature to land on a spot 1/2 mile abeam.

I land a seaplane trimmed up - but I don't land a 152, Arrow or Apache the same way.

I'm a 400-hr CFI now, and have been teaching this method. If anybody's concerned about it - especially you! - I'm all ears.
 
whereisrandall said:
@FastEddieB - I'm guessing you're wondering about the extreme trim - for the forward pressure required on landing and go-around?

I was taught this method by my primary instructor, a high-time CFI. His rationele was to learn to dead-stick every landing (your mileage may vary in other aircraft) so that it's second nature to land on a spot 1/2 mile abeam.

I land a seaplane trimmed up - but I don't land a 152, Arrow or Apache the same way.

I'm a 400-hr CFI now, and have been teaching this method. If anybody's concerned about it - especially you! - I'm all ears.
Click to expand...

OK...

First, I don't see how the rationale about dead-sticking a landing applies - I'm in favor of that but what does that have to do with trim state?

There has already been the concern expressed with going around in a severely out-of-trim condition. I'm on board with that concern. In a go-around things happen fast and your (typically) right hand is going to be busy with throttle/prop/gear/flaps, leaving you to fight the trim one-handed.

In addition, I think most pilots can more accurately apply gradually increasing amounts of back-pressure from a trimmed state in the flare as opposed to starting from a state where they're pushing hard against an out-of-trim yoke or stick and gradually decreasing the amount they're fighting against it.

Finally, instructors pick up on students flying out of trim when the plane drifts off altitude in the same direction every time they're distracted - holding a constant pressure is more difficult than the fingertip pressures an in-trim plane requires, and if a plane will depart its desired state with the mere relaxation of pressure it makes flying harder in general.

If it works for you and your instructor and students, then go for it. But realize it's a highly unusual technique. I have heard of pilots "rolling the trim" back throughout the flare in a nose-heavy plane, and while I don't do that myself I do understand the motivation. "Fighting" the trim through the roundout and flare, not so much.
 
SoCal RV Flyer said:
I make it extremely simple (and it should be said that I'm at a nontowered field with lots of slow rag-and-tube aircraft, so no need to come into the pattern/expedite final at warp speed).

Full flaps before entering the pattern....fly pattern at 70 to 75 KIAS at about 1750 rpm to maintain TPA.
Throttle back to about 1400 rpm abeam the numbers, which gives me the proper sink rate without having to re-trim.
Trim up and reduce power on final to give an over-the fence speed of 60-63 KIAS.
Land.

Wipe all the bugs off the leading edges and windscreen, and call it a day.
Click to expand...

Full flaps before the pattern?!

What would be mighty awkward in many aircraft.



whereisrandall said:
@FastEddieB - I'm guessing you're wondering about the extreme trim - for the forward pressure required on landing and go-around?

I was taught this method by my primary instructor, a high-time CFI. His rationele was to learn to dead-stick every landing (your mileage may vary in other aircraft) so that it's second nature to land on a spot 1/2 mile abeam.

I land a seaplane trimmed up - but I don't land a 152, Arrow or Apache the same way.

I'm a 400-hr CFI now, and have been teaching this method. If anybody's concerned about it - especially you! - I'm all ears.
Click to expand...

I have no idea what exact trim setting I have until after I'm on the ground/water and resetting my trim.

The only time I'm really eyeing my exact trim positions is if I'm flying in/around ice.
 
James331 said:
Full flaps before the pattern?!

What would be mighty awkward in many aircraft.
Click to expand...

Certainly aircraft-dependent. For me & the RV, it lessens the workload and helps me concentrate on "eyes outside" time in the pattern.
 
I do kind of what MAKG does.

Abeam my touch down point I put in first 10 degrees of flaps, reduce speed to 80 kts, 500 fpm descent. Base, next notch of flaps, reduce speed to 70 knots, throttle for 500 fpm. Final, final 90 degrees of flaps (Cherokee 140, I have barn door flaps), 60 knots, throttle for point. With full flaps, the plane requires power all the way to the roundout. Makes for great combined short/soft field though. =D
 
You must log in or register to reply here.
Back
Top